1. Field of Invention
This invention relates generally to animal husbandry, and more particularly to an animal litter box of the type used in the home for the reception of liquid and solid waste matter.
2. Description of Prior Art
What is commonly used for an animal litter box is a receptacle or pan which is filled with particulate, and the particulate is typically a type of absorbent clay matter which absorbs the liquid waste and receives the solid waste matter. A common problem with this type of litter box includes the frequent cleaning of the litter box requiring complete removal of the contents and litter, which is a non-sanitary, odorous and time-consuming task. The frequent cleaning and method of cleaning due to the complete removal and replacement of the litter also requires the use and waste of a lot of litter, which is not economical.
One way that prior art patents have addressed this problem is with a litter pan design that allows the separation of the liquid waste from the solid waste so that the liquid waste is generally confined in a separate receptacle, thereby allowing for less frequent cleaning of the box, in that the saturated clay matter (litter) is no longer filled with the liquid, as the liquid has passed through the matter and into the separate receptacle. There are many problems, however, associated with the designs of the prior art patents.
For example, U.S. Pat. No. 5,184,574 to Kirk et al. discloses a cat litter box which separates the liquid from solid waste with a combination of an upper tray inset into a base pan. The upper tray includes openings for the flow of liquid and is lined with a non-absorbent type of litter, and this upper tray is inset into a base. The base then acts as a reservoir for the liquid that percolates through the openings in the upper tray. This base reservoir is then emptied by carrying the entire upper tray and lower base section to a toilet, whereby a valve connected to the base is turned by a handle, allowing the liquid waste to drain into the toilet. There are many problems with this arrangement. First, the entire unit needs to be carried to a toilet bowl or to another area in order to empty the liquid waste reservoir. This can be a difficult and clumsy arrangement, considering there is also litter in the top portion. Second, there are also potential issues with the use of a valve. The only thing between urine, which is contained in the base, and disaster, is the valve not leaking. This could be an issue as all valves have the potential to leak, especially with continued use, plus the fact that the valve may accidentally be turned while being carried by the person emptying out the liquid waste, or even by an animal as they go to step into the box. Third, in order to clean the actual liquid waste compartment, the litter box must be taken apart. This can create quite a sanitation problem when that top litter tray section is removed for cleaning as the bottom of the litter tray section is soiled, and most individuals, to avoid the placement of the dirty litter tray somewhere in the house, would end up taking the entire assembly outside just to clean the liquid compartment.
U.S. Pat. No. 5,515,812 to Faust discloses a cat litter box with a removable litter screen set on a liquid permeable rack which is then set into a lower waterproofed pan. The litter is then put on top of the rack and when the animal uses it, similar to the cat litter box above, the liquid waste percolates through this liquid permeable portion of the rack down into the pan. This arrangement has similar problems to the prior patent disclosed above. For example, in order to clean the liquid waste compartment, the top rack portion needs to be taken out and placed somewhere, and then the bottom portion would then need to be emptied, such as by carrying it to a toilet bowl. Most likely the only place to possibly clean this would also be outside of the home, similar to the patent above.
U.S. Pat. No. 5,367,984 to Purnell discloses a pet litter box, including a bottom pan for collecting liquid waste and an upper box which closely interfits with the bottom pan so as to contain the odors in the bottom pan, and a litter tray which is supported by the upper box. This litter tray includes an apertured flat sheet which supports a layer of litter. The non-absorbed liquid waste passes down into this bottom pan. The aperture flat sheet provides structural rigidity for supporting the weight of the animal. Again, the primary problem with this device similar to the other devices is that in order to clean the liquid waste compartment, the top upper box needs to be removed and placed somewhere, and then the lower box picked up and carried off for cleaning. This patent also has the issue of stability, as the upper box sits closely and tightly on top of the other box.
U.S. Pat. No. 5,699,754 to Cahajla discloses a litter box which includes a urine collection cavity, and then a litter holding tray which is supported over the urine collection cavity. There also is a disposable element which generally lines the litter holding tray. Both the disposable element and the tray are permeable by liquids so that again liquid waste falls through this litter holding tray and through the disposable element into the lower urine collection cavity. This disposable element again would have to be lifted off before the lower urine collection cavity could be cleaned.
The present invention resolves the problem common to typical litter boxes by also separating out liquid from solid waste, but also addresses the problems inherent in the prior art patents. That is, the present invention allows for a sanitary method of disposing and cleaning the liquid waste collection, while also addressing other issues. With the present invention, there is a reservoir drawer provided for within the base of the device so that it is a simple thing to remove this reservoir drawer and empty it out without having to lift off anything on top of the base and without the need to set the top portions that are lifted off in an area that can be contaminated with the used litter.
Accordingly, several objects of the present invention are to provide an animal litter box that:
a. allows for simple collection and disposal of liquid waste;
b. does not require frequent cleaning, and when it does need to be cleaned, provides for a simple and sanitary method of cleaning;
b. is economical to use as compared to the typical litter box as there is less frequent need to remove and replace the xe2x80x9clitterxe2x80x9d;
c. will contain odors;
d. will be found palatable by and will be used by animals, in particular felines;
c. is simple and economical to manufacture.
These and further objects will be apparent from the following description and drawings of the preferred embodiments thereof.
The present invention is directed to an animal litter box that satisfies the needs for a simple and sanitary to clean, economical, low odor, and timesaving device. The animal litter box comprises a litter tray for supporting a quantity of litter and an animal, that includes an upstanding perimeter wall and liquid permeable bottom means. In a preferred embodiment, the litter tray is an integrally molded single unit of plastic material, and the liquid permeable bottom means is simply a plurality of openings in the bottom through which liquid waste is free to pass. The openings are sized to prevent the litter from passing though, while allowing the flow of liquid waste. The litter box further comprises a drain pan, preferably also of integrally molded plastic, with an upstanding perimeter support wall and a floor sloping inwardly and downwardly from the perimeter wall, said floor including a drain hole, whereby the liquid waste is free to pass. The drain pan supports the litter tray within the drain pan perimeter wall at the point where the drain pan perimeter wall meets the drain pan floor, and the drain pan is sized to receive the litter tray snugly within the drain pan perimeter wall. The litter box further comprises a base, also preferably of integrally molded plastic, with an upstanding perimeter wall that supports the drain pan in the same fashion as the drain pan supporting the litter tray, i.e., the drain pan fits within the perimeter wall base and the upstanding support walls are complementary so that the can removably fit together in a way so that odors are prevented from escaping past the inter-engaged portions of the base and the drain pan. Placed within the base is a removable reservoir drawer for the liquid waste that is positioned within the base, so as to receive the liquid waste flowing through the drain pan hole, and the reservoir drawer is removed and re-positioned through a drawer opening in the base perimeter wall. Preferably, the reservoir drawer contains a recessed handle so that a person removing the liquid waste from the device can simply remove the drawer, carry it over to a toilet, and empty out the liquid waste into the toilet.